This invention relates generally to the field of automated measurement of blood pressure by the oscillometric method. More particularly, this invention relates to a method and apparatus for evaluating and testing the performance characteristics of oscillometric blood pressure monitors and associated cuff.
Oscillometry has become the preferred method for non-invasive blood pressure (NIBP) monitoring. Oscillometric NIBP monitors (oscillometers) are widely used in the Operating Room, and are increasingly used as an alternative to invasive monitoring in the Intensive Care Unit and Coronary Care Unit.
Commercially available oscillometric monitors have proprietary algorithms for predicting the mean, systolic and diastolic pressure from the oscillometric envelope. The more advanced monitors also use complex algorithms intended to reduce noise such as motion artifact. However, no systematic, standardized method is available to evaluate the efficiency of these new devices and algorithms. Static calibration does not test dynamic functionality, human subject comparisons are unreliable and clinical studies are not suitable for routine calibration and performance verification.
U.S. Pat. No. 4,464,123 to Glover et al describes a device for evaluating oscillometers. However, the oscillometer evaluator of the Glover et al patent is capable only of evaluating a specific line of oscillometers manufactured by a specific company under a very specific and artificial set of conditions. The Glover et al device may not yield meaningful test data for oscillometers manufactured by other companies.
U.S. Pat. No. 4,189,936 to Ellis discloses a device for testing invasive blood pressure monitors as opposed to non-invasive oscillometers.